South Australians paying highest water prices in the nation: Essential Services Commission

South Australians have the most expensive drinking water in the nation, according to a report by the state's Essential Services Commission (ESCOSA).

The report found SA Water's "typical residential water bill" jumped by more than 30 per cent to $873 in 2012/13 and was "the highest of all comparable Australian water utilities ... in both 2011/12 and 2012/13."

SA Water’s typical residential water bill was the highest of all comparable Australian water utilities ... in both 2011/12 and 2012/13.

ESCOSA

"Even taking account of relatively high capital expenditure in recent years, the high value of SA Water's asset base appears to be the main driver of high revenues and customer water prices," it said.

SA Water's revenue for water services increased by 15 per cent to almost $920 million, driven by a 25 per cent rise in water tariffs and an 8 per cent rise in demand.

Water Minister Ian Hunter denied the Government was using SA Water as a cash cow.

"South Australia's water catchment is largely the Mt Lofty Ranges. Residential townships and agricultural pursuits are part of that catchment area so we need to treat water to a much higher level than they do in, say, New South Wales or Victoria," he said.

"We demand a very high quality water service, as they do in Sydney and Melbourne, but we have fewer people in South Australia to pay for those costs.

"We will be always be more expensive to provide water than the eastern states."

Mr Hunter said he did not "have the historical data to draw on" to check if that had always been the case.

He said water prices have dropped by 6.4 per cent in the current financial year.